Problem: $\dfrac{2}{4} + \dfrac{1}{2} = {?}$
Solution: ${\dfrac{2}{4}}$ ${\dfrac{1}{2}}$ $+$ ${\dfrac{2 \times 1}{4 \times 1}}$ ${\dfrac{1 \times 2}{2 \times 2}}$ $+$ ${\dfrac{2}{4}}$ ${\dfrac{2}{4}}$ $+$ $ = \dfrac{{2} + {2}}{4} $ $ = \dfrac{4}{4}$